2-Methoxy-5-(6-methoxypyridin-3-yl-imino-methyl)phenol and its transition metal complexes as potent antibacterial agents: Synthesis, characterization, theoretical investigations and biological evaluation

• Published in: Results in Chemistry 2021-01, Vol.3, p.100120, Article 100120
• Main Authors: Mariswamy, Vinusha Honnalagere, Bindya, S., Costa, Renyer A., Prasad, Shashanka K, Shivamallu, Chandan, Begum, S. Muneera, Veerapur, Ravindra, Syed, Asad, Kollur, Shiva Prasad
• Format: Article
• Language: English
• Subjects: Antibacterial activity; DFT calculations; Metal complex; Molecular docking; Schiff base ligand
• ISSN: 2211-7156; 2211-7156
• DOI: 10.1016/j.rechem.2021.100120

•Synthesis of 2-methoxy-5-(((6-methoxypyridin-3-yl)imino)methyl)phenol.•Transition metal complexes were prepared using above Schiff base ligand.•Structure of the prepared compounds are elucidated using spectral techniques.•In vitro antibacterial activity of ligand and metal complexes have been evaluated.•Inhibition of the protein DNA gyrase was evaluated using molecular docking. In this study, we have prepared an imine-based ligand, 2-methoxy-5-((6-methoxypyridin-3-ylimino)methyl)phenol (MIMP) and its Cu(II), Ni(II) and Zn(II) complexes in 2:1 stoichiometric ratio (2MIMP : Metal). The structure of obtained ligand and its metal complexes were elucidated with the aid of FT-IR, UV–Visible, NMR (1H and 13C) and mass spectra. Further, all the structures were analyzed via density functional theory (DFT) approach at B3LYP/LanL2DZ/6-311++G(2d,p) level, with HOMO-LUMO energies, geometric parameters, reactivity properties and electronic excitations obtained through TD-DFT calculations. Antibacterial activity of MIMP ligand and metal complexes have been evaluated via in vitro assays. In addition, the inhibition of the protein DNA gyrase-DNA complex was evaluated using molecular docking calculations, and the results revealed that biological accessibility of the metal complexes was better than ligand.